Durable, flexible panels are known. Such panels are incorporated into roll-up doors which are typically fabricated from flexible fabric or pivotally connected horizontal metal slats. The roll-up doors fabricated from flexible fabric are undesirable because they are not sufficiently cut-proof or puncture-proof and therefore are susceptible to vandalism.
While the doors made from connected horizontal slats are sufficiently strong, they are relatively expensive to manufacture because of the difficulty in assembling the interconnected horizontal slots. Further, the roll-up doors made from connected horizontal slats are flexible in a horizontal direction only so they can be rolled up onto a horizontal roll disposed at the top of the door opening. However, these types of roll-up doors are not flexible in a direction that extends outward or inward from the plane of the door. Therefore, these doors are not flexible if an automobile or other structure bumps or engages the door when the door is closed. Often, the metal slots become bent which makes it difficult to extend and retract the door. Further, when one or more of the horizontal slats of the door are sufficiently bent, the entire door or curtain must be replaced.
Another use for a strong material for connecting purposes are vestibule connections for adjoining ends of two railroad car sections. Currently, such vestibule connections are fabricated from accordion-like structures that are a combination of metal frames connected by a webbing that is fabricated from rubber or a combination of rubber and durable fabric. Also, the accordion-like connecting structures can be fabricated entirely from metal.
The currently available vestibule connections suffer from a number of deficiencies. First, if rubber or a fabric material is used to connect the frame components together, the rubber combination of rubber and fabric can be easily cut or damaged by vandals. This is particularly problematic for trains that are transporting valuable commodities, such as luxury automobiles. Typically, in railroad car sections designed exclusively to transport automobiles, the vestibule connection or flexible connection between the railroad cars is the only means of preventing unauthorized entry into the car sections themselves. Accordingly, by fabricating the vestibule connections from rubber or a combination of rubber and fabric, the vestibule connections and therefore the car sections themselves are susceptible to vandalism and unauthorized entry.
Another disadvantage associated with currently available vestibule connections is reliance upon the use of metal frame members in the accordion-like structure. Any damage to these metal frame members often requires replacement of the entire vestibule connection.
Accordingly, there is a need for an improved flexible and very strong material that is resistant to cutting and puncturing. Such an improved material will lead to improved roll-up type doors as well as to improved vestibule connections or covered connections for adjacent railroad car sections. It is also anticipated that such an improved flexible and durable material would have many other applications as well.